In an spectrometer for charged particles, or in an imaging system for charged particles, the adjustment of the relative position and/or the intensities of the individual components is conventionally carried out by means of mechanical adjustments in order to ensure that the beam, or bundle, of charged particles passes through the apparatus in the desired manner. Whereas focussing and adjustment by mechanical means is associated with major expense, there has been a trend towards carrying out the adjustment by means of electric and/or magnetic correcting elements, in order both to deflect the particle bundle and to twist its optical axis in such a manner that it finally passes through all the components of the imaging system or, as the case may be, of the spectrometer, at the correct point, on the one hand, and with the correct and desired orientation, on the other hand.
The object of the invention is accordingly to indicate an arrangement and a process for adjusting an imaging system for bundles of charged particles, or for adjusting a spectrometer for bundles of charged particles, this arrangement and process enabling the required regulation and ajustment to be carried out in a simple and desirable manner.